BACKGROUNDThe disclosed subject matter relates generally to hydrocarbon production and, more particularly, to a maintenance condition sensing device including sensors, a communication device, and an embedded processor for coupling to a component defining a flow passage for determining a maintenance condition of the component.
Components used for hydrocarbon exploration requires a routine time-based maintenance schedule to determine compliance. Inspections are commonly performed to assess corrosion, erosion, seal integrity or fatigue issues. However, the correct interval between maintenance depends on process conditions and operator requirements, which are not always readily available. Moreover, inspection tools available for testing these components are expensive and difficult to handle/operate and typically require the parts to be removed from field and tested in a warehouse or laboratory setting. In most cases, the testing involves the use of sophisticated lab equipment operated by certified personnel to accurately perform tests, collect information and analyze the data to determine the operability of the component. The removal of components for testing and analysis is expensive and time consuming. If the maintenance interval is too short, costs increase, while, if the maintenance interval is too long, component degradation may occur and service life and safety may be compromised. In addition, situations occur where the process data is not recorded accurately due to inefficient data logging methodologies and human errors. There are also instances where dangerous events such as pressure surges (spikes) or high shocks above acceptable limits are not captured by traditional data loggers.
This section of this document is intended to introduce various aspects of art that may be related to various aspects of the disclosed subject matter described and/or claimed below. This section provides background information to facilitate a better understanding of the various aspects of the disclosed subject matter. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art. The disclosed subject matter is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.
SUMMARYThe following presents a simplified summary of the disclosed subject matter in order to provide a basic understanding of some aspects of the disclosed subject matter. This summary is not an exhaustive overview of the disclosed subject matter. It is not intended to identify key or critical elements of the disclosed subject matter or to delineate the scope of the disclosed subject matter. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is discussed later.
One aspect of the disclosed subject matter is seen in a method for monitoring a maintenance condition of a component. The method includes coupling a sensing device to the component. The sensing device includes at least one non-intrusive data sensor and an on-board processing complex including a wireless communication device and being coupled to the at least one non-intrusive data sensor. Data from the at least one non-intrusive data sensor is processed in the on-board processing complex using a maintenance model to determine a maintenance condition metric for the component. The maintenance condition metric is transmitted to a remote system using the wireless communication device.
Another aspect of the disclosed subject matter is seen in a method including coupling a sensing device to a component. The sensing device has a flexible body, at least one non-intrusive data sensor coupled to the flexible body, and an on-board processing complex including a wireless communication device coupled to the at least one non-intrusive data sensor and to the flexible body. Data from the at least one non-intrusive data sensor is processed in the on-board processing complex using a maintenance model to determine a maintenance condition metric for the component. The maintenance condition metric includes a remaining useful life metric. An operational recommendation is generated based on the remaining useful life metric. The operational recommendation is transmitted to a remote system using the wireless communication device.
Yet another aspect of the disclosed subject matter is seen in a device including a flexible body, at least one non-intrusive data sensor coupled to the flexible body, and a processing complex including a wireless communication device coupled to the at least one non-intrusive data sensor and the flexible body. The processing complex is to process data from the at least one non-intrusive data sensor using a maintenance model to determine a maintenance condition metric for a component to which the device is coupled and transmit the maintenance condition metric to a remote system using the wireless communication device.
BRIEF DESCRIPTION OF THE DRAWINGSThe disclosed subject matter will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1 is a simplified diagram of a maintenance warning system, according to some embodiments disclosed herein;
FIG. 2 is a diagram of the maintenance warning system ofFIG. 1 prior to installation, according to some embodiments disclosed herein; and
FIG. 3 is a flow diagram of a method for determining a maintenance condition of a component, according to some embodiments disclosed herein.
While the disclosed subject matter is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the disclosed subject matter to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosed subject matter as defined by the appended claims.
DESCRIPTION OF EMBODIMENTSOne or more specific embodiments of the disclosed subject matter will be described below. It is specifically intended that the disclosed subject matter not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. Nothing in this application is considered critical or essential to the disclosed subject matter unless explicitly indicated as being “critical” or “essential.”
The disclosed subject matter will now be described with reference to the attached figures. Various structures, systems and devices are schematically depicted in the drawings for purposes of explanation only and so as to not obscure the disclosed subject matter with details that are well known to those skilled in the art. Nevertheless, the attached drawings are included to describe and explain illustrative examples of the disclosed subject matter. The words and phrases used herein should be understood and interpreted to have a meaning consistent with the understanding of those words and phrases by those skilled in the relevant art. No special definition of a term or phrase, i.e., a definition that is different from the ordinary and customary meaning as understood by those skilled in the art, is intended to be implied by consistent usage of the term or phrase herein. To the extent that a term or phrase is intended to have a special meaning, i.e., a meaning other than that understood by skilled artisans, such a special definition will be expressly set forth in the specification in a definitional manner that directly and unequivocally provides the special definition for the term or phrase.
Referring now to the drawings wherein like reference numbers correspond to similar components throughout the several views and, specifically, referring toFIG. 1, the disclosed subject matter shall be described in the context of a maintenancecondition sensing device100 for attachment to a component105 (e.g., pipe, wellhead, riser, flow line, Christmas tree, pump, manifold, valve, connector, choke, etc.) for monitoring the maintenance condition and process parameters of thecomponent105. Thecomponent105 may be installed in a surface environment or a subsea environment.FIG. 2 illustrates the maintenancecondition sensing device100 prior to installation on thecomponent105. In some embodiments, thecomponent105 is a tubular member. The term tubular does not require that the component has a circular cross-section, but rather that there is generally a wall that creates a pressure boundary relative to an interior cavity (e.g., flow passage).
The maintenancecondition sensing device100 includes aflexible body110 to which a plurality of sensors115 (individually enumerated as115A-115I inFIG. 2) and aprocessing complex120 are mounted (e.g., attached to thebody110 or encapsulated by a portion of the body110). Thesensors115 are connected to theprocessing complex120 bylines125, and one or more sensors115 (e.g.,sensors115A-115D) may be interconnected bylines130. Thelines125,130 may be attached to or embedded in theflexible body110. The number, type and arrangement of thesensors115A-115I may vary. The maintenancecondition sensing device100 may be interfaced with thecomponent105 by wrapping theflexible body110 around thecomponent105. In general, thesensors115 are non-intrusive sensors employed to determine the process and physical conditions of thecomponent105. Thesensors115H,115I may be circumferential sensors in that they may wrap around most or all of the circumference of thecomponent105 when theflexible body110 is wrapped around thecomponent105. In some embodiments, the length of theflexible body110 may be selected so as to wrap around thecomponent105 one or more times, and thesensors115 may be arranged to account for the intended interface area.
Ahousing135 may be provided to enclose theflexible body110 and its attachments. Thehousing135 may be a clamp type device including ahinge140 and extendingplates145 that may be engaged with one another using a fastener150 (e.g., nut and bolt). Thehousing135 may seal to thecomponent105 to isolate theflexible body110 from the external environment. A protective wrap (not shown) may be provided between theflexible body110 and thehousing135 and/or over thehousing135 to provide additional protection and/or sealing.
FIG. 1 includes a simplistic block diagram of theprocessing complex120. Theprocessing complex120 includes, among other things, aprocessor140, amemory145, a location module150 (e.g., GPS module, WiFi RSSI location estimator, gyroscope, compass, etc.), atransceiver155, anantenna160, and a power supply165 (e.g., battery, solar unit, etc.). The plurality ofsensors115 are coupled to theprocessor140. Thememory145 may be a volatile memory (e.g., DRAM, SRAM) or a non-volatile memory (e.g., ROM, flash memory, hard disk, etc.). Thetransceiver155 transmits and receives signals via theantenna160, thereby defining a wireless communication device. Thetransceiver155 may include one or more radios for communicating according to different radio access technologies, such as cellular, Wi-Fi, Bluetooth®, etc. Theprocessor140 may execute instructions stored in thememory145 and store information in thememory145, such as the results of the executed instructions. Theprocessing complex120 may implement amaintenance prediction unit170 that employs the outputs of thesensors115 in conjunction with amaintenance model175 to determine a maintenance condition metric for thecomponent105 and perform portions of amethod300 shown inFIG. 3 and discussed below. Themaintenance prediction unit170 may communicate determined maintenance condition metrics to aremote system180 via thetransceiver155. Although thesensors115 are illustrated as being directly connected to theprocessing complex120, in some embodiments, one or more of thesensors115 may connect to theprocessing complex120 wirelessly via thetransceiver155 andantenna160.
Example sensors115 that may be included in the maintenancecondition sensing device100 include a vibration sensor115(1), a temperature sensor115(2), a pressure sensor115(3), a strain sensor115(4), an electrical sensor115(5), (e.g., resistance, voltage, current, electrical field, magnetic field), etc. Thesensors115A-115I illustrated inFIG. 2 may be selected from one or more of the sensors115(1)-115(5) shown inFIG. 1. In general, thesensors115 may be optical, electrical, piezoelectric, magnetic, magnetorestrictive, mechanical, etc.
FIG. 3 is a flow diagram of amethod300 for determining a maintenance condition of acomponent105, according to some embodiments disclosed herein. Inmethod block305, the maintenancecondition sensing device100 is coupled to thecomponent105. In some embodiments, the sensing device includes at least onenon-intrusive data sensor115, and an on-board processing complex120 including awireless communication device155 coupled to the at least onedata sensor115.
Inmethod block310, data from the data sensor(s)115 is processed in the on-board processing complex120 using amaintenance model175 to determine a maintenance condition metric for thecomponent105. There are various techniques that themaintenance prediction unit170 may employ to determine maintenance condition metrics for thecomponent105. Themaintenance prediction unit170 employs the outputs of thesensors115 in conjunction with themaintenance model175 using techniques developed based on finite element analysis (FEA), computational fluid dynamics (CFD), etc., to determine maintenance conditions relevant to thecomponent105, such as internal pipe pressure, fatigue, crack presence, flow rate, erosion, corrosion, temperature, sediment build-up, etc. Machine learning algorithms may be employed to re-learn, optimize, and adapt to changing process and environmental conditions to build new correlation models in the field.
In one example, strain may be measured based on input from the pressure sensor115(3) or the strain sensor115(4). Themaintenance model175 may include a model that linearly correlates strain with pressure if the input from the pressure sensor115(3) is employed. The measured or derived strain may be employed in themaintenance model175 to estimate wall thickness using the relationship:
where,
- εθθ is the hoop strain;
- εααis the axial strain;
- b is the outer diameter of the pipeline;
- a is the inner diameter of the pipeline;
- E is the Young's Modulus;
- k is the strain constant; and
- G is a constant determined by the pipe geometry.
Hence, by monitoring the value of the constant, E, the wall-thickness can be implicitly monitored. Assuming G is constant, the value of E will remain the same as long as the wall-thickness of the pipeline remain the same. However, any change in the material of the pipeline, mostly internal diameter change, will cause the value of E to change indicating the maintenance condition of the pipeline.
Themaintenance model175 may also include a model that correlates vibration frequency to flow rate. The flow rate may be used to track the duty cycle of thecomponent105 to estimate the erosion effects of the duty cycle on the wall thickness based on knowledge of the process fluid being conducted through thecomponent105. Hence, for a given design or initial wall thickness, themaintenance prediction unit170 may monitor the flow conditions (duty cycle—flow rate over time) and estimate a reduction in the wall thickness over time. Hence, wall thickness may be estimated based on strain, duty cycle or both. The computed wall thickness may represent a maintenance condition metric.
In some embodiments, themaintenance model175 includes a Remaining-Useful-Life (RUL) model that employs the measured and calculated parameters, such as wall thickness, flow rate, duty cycle, vibration, etc., to estimate a RUL metric for thecomponent105. Thecomponent105 may have an expected design useful life (DUL). The DUL may be established for a new component or for a serviced component, which may differ. The RUL metric may further be examined by evaluating magnetic and acoustic properties of the component to determine residual stress. For example, the magnetic field distribution on pristine components is uniform and aligned by the earth's magnetic field during manufacture. This field distribution becomes disoriented or non-uniform with stress induced grain boundary movements. Monitoring this non-uniformity or change gives insights into fatigue of the material. Similarly, the acoustic wave propagation properties change with microstructure changes within the material.
In some embodiments, themaintenance prediction unit170 may be employed to determine a maintenance condition of a different component near thecomponent105 to which the maintenancecondition sensing device100 is mounted. For example, if the maintenancecondition sensing device100 is mounted to a pipe near one or more pumps, themaintenance model175 may determine a maintenance condition of a particular pump or a maintenance condition of the group of pumps, such as the pumps being out of synch with one another. By monitoring the pump pressure pulses on the component105 (e.g., flowline), a signature pressure pulse pattern is expected depending on the number of pumps, the type of pump (e.g., Triplex, Quintuplex), and how the pumps are connected. By monitoring the signature, themaintenance prediction unit170 can determine if the pumps are not performing as expected. Also, if a choke downstream is activated, themaintenance prediction unit170 can determine the true choke position by determining the pressure in the lines and the flow rate to identify a maintenance condition where the choke is worn out. In another example, each component in the field has a unique vibration frequency. By comparing the normal operating frequencies to malfunction induced operating frequencies, themaintenance prediction unit170 may determine a location of a fault or a faulty component.
One type of model that may be used to determine a maintenance condition metric is a recursive principal components analysis (RPCA) model. Maintenance condition metrics are calculated by comparing data for all parameters from the sensors and derived parameters generated based on the sensor readings to a model built from known-good data. The model may employ a hierarchy structure where parameters are grouped into related nodes. The sensor nodes are combined to generate higher level nodes. For example, data related to wall thickness (e.g., strain, vibration, flow rate, duty cycle) may be grouped into a higher level node, and nodes associated with the other maintenance condition parameters may be further grouped into yet another higher node, leading up to an overall node that reflects the overall maintenance condition or RUL of thecomponent105. The nodes may be weighted based on perceived criticality in the system. Hence, a deviation detected on a component deemed important may be elevated based on the assigned weighting. For an RPCA technique, as is well known in the art, a metric may be calculated for every node in the hierarchy, and is a positive number that quantitatively measures how far the value of that node is within or outside 2.8-σ of the expected distribution. An overall combined index may be used to represent the overall maintenance condition of thecomponent105. Themaintenance model175 may also employ data other than the data from thesensors115 in determining the intermediate or overall maintenance condition metrics. For example, real time production data and/or historical data may also be employed. The historical data may be employed to identify trends with thecomponent105.
In some embodiments, themaintenance prediction unit170 may generate an operational recommendation based on the maintenance condition metric(s). For example, the operational recommendation may be a graded indicator, such as red for reduced RUL, yellow for intermediate RUL, and green for extended RUL. The operational recommendation may also be generated based on lower level maintenance condition metrics, such as estimated wall thickness, duty cycle, etc. The metric(s) contributing to the grade may be provided with the recommendation. The operational recommendation may indicate a deviation from an allowed condition and/or a data trend that predicts an impending deviation, damage or failure, such as a crack or a buildup of sediment in thecomponent105.
Inmethod block315, themaintenance prediction unit170 transmits the operational recommendation and/or the computed maintenance condition metric(s) to theremote system180 via thetransceiver155 and theantenna160. Since themaintenance prediction unit170 receives the sensor data and calculates the maintenance condition metrics on board, the data required to be sent by thetransceiver155 is significantly reduced when compared to a system that transmits sensor data to a remote location for analysis. This approach minimizes data transmission and, thus, power consumption, thereby extending the life of the power supply165 (e.g., battery).
In some embodiments, themaintenance prediction unit170 periodically communicates an overall maintenance condition metric, such as RUL, to theremote system180. The update frequency may vary depending on the particular implementation (e.g., hourly, daily, etc.) If specific alarm conditions are met for one of the maintenance condition metrics, such as vibration, wall thickness, etc., an alert message may be sent immediately allowing corrective action to be taken. Themaintenance prediction unit170 may generate one or more logs of the process conditions encountered by thecomponent105 based on the received data and the analysis performed to generate the maintenance condition metrics. Themaintenance prediction unit170 may send portions of the log data to theremote system180 on request or based on the identification of problem conditions.
In some embodiments, themaintenance prediction unit170 also employs location data to allow tracking of thecomponent105 or movement of the maintenance condition sensing device100 (i.e., to a different component). In some embodiments, themaintenance prediction unit170 tracks its actual geospatial location using GPS data or received signal strength data from a data network. In this manner, theremote system180 may construct a map that tracks multiple components by location. In addition, the maintenance conditions of components without monitoring hardware may be estimated based on the maintenance condition metrics of nearby monitored components. In some embodiments, thelocation module150 may only track local movement indicating that the maintenancecondition sensing device100 has been moved. If themaintenance prediction unit170 determines that the maintenancecondition sensing device100 has been moved, various model parameters may be reset (e.g., erosion, duty cycle, wall thickness). Self-optimizing fault tolerant (SOFT) algorithms may be employed to re-learn on-board processing algorithms for the specific location.
In some embodiments, certain aspects of the techniques described above may be implemented by one or more processors of a processing system executing software. Themethod300 described herein may be implemented by executing software on a computing device, such as theprocessing complex120 ofFIG. 1, however, such methods are not abstract in that they improve the operation of thecomponent105. Prior to execution, the software instructions may be transferred from a non-transitory computer readable storage medium to a memory, such as thememory145 ofFIG. 1.
The software may include one or more sets of executable instructions stored or otherwise tangibly embodied on a non-transitory computer readable storage medium. The software can include the instructions and certain data that, when executed by one or more processors, manipulate the one or more processors to perform one or more aspects of the techniques described above. The non-transitory computer readable storage medium can include, for example, a magnetic or optical disk storage device, solid state storage devices such as Flash memory, a cache, random access memory (RAM) or other non-volatile memory device or devices, and the like. The executable instructions stored on the non-transitory computer readable storage medium may be in source code, assembly language code, object code, or other instruction format that is interpreted or otherwise executable by one or more processors.
A computer readable storage medium may include any storage medium, or combination of storage media, accessible by a computer system during use to provide instructions and/or data to the computer system. Such storage media can include, but is not limited to, optical media (e.g., compact disc (CD), digital versatile disc (DVD), Blu-Ray disc), magnetic media (e.g., floppy disc, magnetic tape or magnetic hard drive), volatile memory (e.g., random access memory (RAM) or cache), non-volatile memory (e.g., read-only memory (ROM) or Flash memory), or microelectromechanical systems (MEMS)-based storage media. The computer readable storage medium may be embedded in the computing system (e.g., system RAM or ROM), fixedly attached to the computing system (e.g., a magnetic hard drive), removably attached to the computing system (e.g., an optical disc or Universal Serial Bus (USB)-based Flash memory), or coupled to the computer system via a wired or wireless network (e.g., network accessible storage (NAS)).
The particular embodiments disclosed above are illustrative only, as the disclosed subject matter may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the disclosed subject matter. Accordingly, the protection sought herein is as set forth in the claims below.